2014-11-28 (F) Switchable Voltage Serial Adapter COMPLETED

There are two different Arduino boards used in the Arduino Laser Tag project one of which is 5V and the other is 3.3V. The previous solution was to use two different adapter boards which were inexpensive. Unfortunately these were knock-off chips which were not supported by modern drivers so a genuine FTDI chip was ordered from a reputable retailer but was five times more expensive than either of the previously purchased boards. Instead of buying two a switch was installed to switch between the voltages.

Enough background
----------

A USB<->Serial adapter was purchased from Sparkfun.com in order to get a genuine FTDI chip usable with modern drivers. Imitation chips often fail to install FTDI drivers. The adapter was selectable between 3.3V and 5V by creating a solder bridge between two of three solder pads. The default was 5V so a solder trace had to be cut and was done with a snap-blade knife.

 Severed trace between common pad and 5V pad

Snap knife

A single-pole double-throw (SPDT) switch was made from a (DPDT) switch by cutting away the pins from one of the poles. This was only done to make space for wire bending. Any SPDT switch with maintained contacts could be used. Three scrapped ethernet wires were salvaged cut, stripped, tinned and soldered to the switch pins. The wire, 26AWG, was too large to fit on the solder pads so smaller 30AWG (???) enameled magnet wire was selected. The ends were scraped to remove the enamel and soldered to the switch. Pieces of shrink tube where used to cover exposed parts of the wire. The other ends were soldered to the voltage selector pads on the board. The common pin of the switch went to the common voltage selector pad and the other switch leads went to the other pads on the board. It tested well on a 3.3V Arduino and drivers installed automatically.

 Leads cut from switch

 Two wire diameters next to one another

Enameled wires soldered to board

Switch bent around and zip tied to board

Board appearing in device manager


Journal Page

The rest of the posts for this project have been arranged by date.

A list showing of all the final posts of COMPLETED projects.


This disclaimer must be intact and whole. This disclaimer must be included if a project is distributed.

All information in this blog, or linked by this blog, are not to be taken as advice or solicitation. Anyone attempting to replicate, in whole or in part, is responsible for the outcome and procedure. Any loss of functionality, money, property or similar, is the responsibility of those involved in the replication.

All digital communication regarding the email address 24hourengineer@gmail.com becomes the intellectual property of Brian McEvoy. Any information contained within these messages may be distributed or retained at the discretion of Brian McEvoy. Any email sent to this address, or any email account owned by Brian McEvoy, cannot be used to claim property or assets.

Comments to the blog may be utilized or erased at the discretion of the owner. No one posting may claim claim property or assets based on their post.

This blog, including pictures and text, is copyright to Brian McEvoy.

Comments

Post a Comment